How long will pads last before I should change them?

 The life span of Evaporative Cooling Pads is greatly dependant on how often and for how long each day the cooler is used as well as the quality of supply water.  It stands to reason that each pad would have a similar amount of workable hours in them and therefore the more often the cooler is in use the shorter the life span of the pads would be.  The quality of the supply water also has a great effect on life span.  Where the supply is of a good quality municipal type water the pads will last longer.  If the water supply is of poor quality or “hard” type water as found from boreholes etc, the lifespan of the pads will be shorter.  This is because with “hard” water there is a larger amount of solids and calcium left behind during the evaporation process and these will eventually restrict the airflow through the flutes of the pads.

In good conditions with normal use Evaporative Cooling Pads usually last from 2 – 5 years, but in areas with poor water quality and where the coolers are used extensively the pads will need be changed far more frequently.

Is it important to dump the sump water periodically?

Periodic dumping of the sump water is of huge importance in prolonging the life of the pads.  Solids left behind through the process of evaporation need to be purged from the sump as often as possible.  In areas with good quality water it may be sufficient to dump the sump water every 5 hours but where the supply water quality is poor it is best to dump the water more frequently – even at 1 hour intervals in extreme cases.  Good quality Evaporative Coolers will allow for this dumping of water and it is vital for the person replacing the pads to check that this dumping cycle is working correctly.  Some Evaporative Coolers use a bleed off type system which allows a slow but continues purging of a small amount of water but this system is by no means as effective as dumping the entire sump of water periodically.

What is the water usage of Evaporative Cooling pads?

Evaporative Cooling Pads, when in use, require a constant supply of water for the evaporation process to take place.  The amount of water used depends on two things; firstly the temperature and humidity of the outside ambient air and secondly the quantity of air passing through the Evaporative Cooling Pads.  Example figures would be as follows:  

Assume outside conditions of 30˚ C dry bulb, 35% humidity.

Water usage = approx. 18 litres per hour for every m³/s of air passing the pad.

*assuming the air speed across the pad is correct to obtain 90% cooling efficiency*

Do Evaporative Cooling Pads cool in humid areas?

Evaporative Cooling Pads work best in hot and dry ambient conditions.  The amount of water vapour that can be taken into the air during the evaporation process is limited by how much space there is in the air for that moisture.  In air that is already very humid this space is limited and only some of the water can be evaporated into the air.  The result of this is that the cooling effect is lower.  The combination of the outside ambient air’s dry bulb temperature and humidity at the point in time that the cooling is taking place will determine the resultant temperature drop that can be achieved by the pad.  To plot specific results for specific conditions please click here to see What is Evaporative Cooling on our Cool Breeze website or ask one of our friendly staff to help you.

Can Evaporative Cooling Pads be cleaned?

Generally speaking, Evaporative Cooling Pads can not be cleaned.  This is because during the process of evaporation the calcium deposits that are left behind fix themselves to the pad surfaces and when cleaning the force required to remove these particles would tend to damage the pad structure.  The use of running water from a hose pipe, as long as the force is not too strong, can be used to rinse larger loose particles from the pad but this will not offer complete cleaning.  With Evaporative Cooling Pads the concept of “prevention is better than cure” would apply and it is best to make sure that the internal water management systems of the Evaporative Cooler are working correctly and that the cooler is correctly dumping its water as required.